Search PubMed⌕ Search

Biomedical subjects

F Hahn

Publications and source records attributed to F Hahn.

At least 19 recordsLinked to original sources
PubMed2005

[Diagnosis and therapy of post-traumatic stress disorders in childhood and adolescence. Responsibilities of the child and adolescent psychiatric trauma outpatient clinic].

This article presents an overview of the etiology, clinical characteristics, assessment, and treatment of PTSD in children and adolescents. Diagnostic criteria of DSM-IV and ICD-10 for PTSD in adults may not adequately describe this disorder especially in toddlers and preschool children, because specific PTSD symptoms may vary according to the developmental stage of the child. Prevalence of PTSD in adolescence is similar to that in adulthood. Children who exhibit high degrees of psychopathology before traumatic exposure, who are exposed to high levels of trauma for an extended period, or who directly experienced the event face a high risk to develop PTSD and other later adverse outcomes. Parental support and other social factors also emerge as strong predictors of differential risk among traumatized children. Cognitive-behavioral therapy is a well-assessed intervention strategy recommended for children and adolescents with PTSD while there are no controlled trials of pharmacological treatments. The outpatient clinic for traumatized children and adolescents of the University Clinic of Aachen is introduced and clinical characteristics of children seeking help are described. In addition, the social network and cooperating services are illustrated.

Adolescent↗
PubMed2004

Transmission disequilibrium studies in children and adolescents with obsessive-compulsive disorders pertaining to polymorphisms of genes of the serotonergic pathway.

Pharmacological and challenge study data showed an involvement of the serotonergic system in the development of obsessive-compulsive disorder (OCD). We studied transmission disequilibrium of polymorphisms in three candidate genes of the serotonergic pathway in 64 trios comprising patients with early onset OCD and both of their parents. Polymorphisms of the following genes were studied: tryptophan hydroxylase 1 (rs1800532), serotonin transporter (polymorphism in the promoter region; 5-HTTLPR) and the serotonin 1 B receptor (rs6296). This is, to our knowledge, one of the first family based association studies pertaining to children and adolescents with OCD. We did not detect transmission disequilibrium of the investigated polymorphisms in OCD. Hence, these polymorphisms do not play a major role in the genetic predisposition to early onset OCD.

Adolescent↗
PubMed2001

Plasma levels of soluble CD14 and tumor necrosis factor-alpha type II receptor correlate with cognitive dysfunction during human immunodeficiency virus type 1 infection.

The relationship between monocyte immune responses and cognitive impairment during progressive human immunodeficiency virus type 1 (HIV-1) infection was investigated in 28 subjects receiving highly active antiretroviral therapy. The mean+/-SEM CD4(+) T lymphocyte count and virus load for all patients were 237+/-41 cells/mm(3) and 77,091+/-195,372 HIV-1 RNA copies/mL, respectively. Levels of soluble tumor necrosis factor-alpha type II receptor (sTNF-RII) and soluble CD14 (sCD14) were measured in plasma by ELISA and were correlated with results from neuropsychological, magnetic resonance imaging, and magnetic resonance spectroscopy tests. Plasma sCD14 and sTNF-RII levels were elevated in subjects with cognitive impairment and in those with brain atrophy. Furthermore, both factors were correlated with spectroscopic choline:creatine ratios. These findings support the idea that peripheral immune responses are linked to cognitive dysfunction during advanced HIV-1 disease.

Adult↗
PubMed2000

Ultrastructural evidence of fibrillar beta-amyloid associated with neuronal membranes in behaviorally characterized aged dog brains.

The aged dog brain accumulates beta-amyloid in the form of diffuse senile plaques, which provides a potentially useful in vivo model system for studying the events surrounding the deposition of beta-amyloid. We used postembedding immunocytochemistry at the electron microscopic level to determine the subcellular distribution of beta-amyloid 1-40 and beta-amyloid 1-42 peptides in the prefrontal and parietal cortex of behaviorally characterized dogs ranging in age from one to 17 years. Immunogold particles signaling beta-amyloid 1-42 occurred over intracellular and extracellular fibrils that were approximately 8 nm in width. Intracellular beta-amyloid 1-42 fibrils were found in close proximity to glial fibrillary acidic protein fibers within astrocytes, but only in cells with signs of plasma membrane disruption. Neuronal labeling of beta-amyloid 1-42 appears to be associated with the plasma membrane. Membrane-bound beta-amyloid 1-42 occurs in the form of fine fibrils that are embedded in the dendritic membrane and appear to project into the extracellular space as determined by quantitative analysis of the immunogold particle distribution. Bundles of beta-amyloid 1-42 were also closely associated and/or integrated with degenerating myelin sheaths of axons. In one dog that was impaired on several cognitive tasks, extensive beta-amyloid 1-42 deposition was associated with microvacuolar changes and vascular pathology. The present findings suggest that beta-amyloid 1-42 may be generated at the dendritic plasma membrane as well as in intracellular compartments. The close association between beta-amyloid 1-42 and destroyed myelin suggests one possible new mechanism by which beta-amyloid 1-42 induces neurodegeneration.

Amyloid beta-Peptides↗
PubMed2000

A case of primary amenorrhea, diabetes and anosmia.

This case details a patient with primary amenorrhea with an unusual cause. She presented at age 16 with short stature, minimal sexual development and no prior menses. Her history was significant for poorly controlled type 1 diabetes. She had been evaluated previously for growth hormone deficiency, and had received a short course of growth hormone therapy. Of greatest significance was the fact that she had also had a decreased sense of smell since her youth. Although a previous computerized tomography scan had been reported as normal, follow-up magnetic resonance imaging demonstrated the absence of olfactory bulbs. Smell testing confirmed the absence of smell and testing of gonadotropin releasing hormone demonstrated an inadequate response. All of these features suggested Kallmann syndrome. This syndrome commonly presents with delayed onset of puberty and decreased or absent sense of smell. There are also many associated features, and the disease is remarkable for its great genotypic and phenotypic variability. Current understanding of its pathogenesis, the commonly associated features of Kallmann syndrome and the impact of diabetes on growth and sexual development are reviewed.

Adolescent↗
PubMed1999

Direct identification of ventrointermediate nucleus of the thalamus on magnetic resonance and computed tomography images.

OBJECTIVE: The ventro-intermediate (Vim) nucleus of the thalamus is a commonly used target for the treatment of tremor. The thalamic fasciculus contains myelinated fibers, believed to play a role in the generation of tremor, that converge into a dense bundle at the inferior aspect of the Vim nucleus, making it visible on magnetic resonance (MR) and computed tomography (CT) images. This structure, therefore, can be visualized directly and targeted for thalamotomy. METHODS: Thalamotomies were performed on nine patients (who have a follow-up of 13-23 months) with parkinsonian and essential tremors using MR and CT images. The tremor target was hypointense on MR images obtained in inversion recovery sequence and hypointense on CT images. It was therefore visualized, directly targeted, and probed. Stimulation studies were done to physiologically confirm accuracy of the probe placement and then a radiofrequency lesion was made. RESULTS: Stimulation of the target identified as the Vim nucleus on MR and CT images produced responses similar to those expected from the Vim nucleus. After this site was lesioned tremor disappeared in all nine patients. CONCLUSION: The Vim nucleus of the thalamus is visible on MR and CT images. Destruction of this target abolishes parkinsonian and essential tremors.

Aged↗
PubMed1998

Suppression of inflammatory neurotoxins by highly active antiretroviral therapy in human immunodeficiency virus-associated dementia.

A human immunodeficiency virus type 1 (HIV)-seropositive, antiretroviral-naive patient presented with significant cognitive dysfunction. Neuropsychologic, neuroradiologic, immunologic, and virologic studies confirmed HIV-associated dementia (HAD). After 12 weeks of highly active antiretroviral therapy (HAART) with ibuprofen, dramatic improvements were demonstrated in neurologic function and were sustained for > 1 year. HIV-1 RNA in cerebrospinal fluid (CSF) decreased from 10(5) to 10(4) copies/mL after 4 weeks. After 20 weeks of therapy, plasma viremia decreased from 10(6) copies/mL to undetectable (< 96 copies/mL). Assays of neurotoxins (tumor necrosis factor-alpha, quinolinic acid, and nitric oxide) in plasma and CSF were considerably elevated at presentation and significantly decreased after therapy. Baseline plasma and CSF demonstrated neurotoxic activities in vitro, which also reduced markedly. These data, taken together, support the notion that HAD is a reversible metabolic encephalopathy fueled by viral replication. HAART used with nonsteroidal antiinflammatory agents leads to the suppression of inflammatory neurotoxins and can markedly improve neurologic function in HAD.

AIDS Dementia Complex↗
PubMed1998

Anatomical structures in the Leksell pallidotomy target.

OBJECTIVE: Because interruption of pallidal outflow signals by pallidotomy is believed to play an important role in the motor improvement in Parkinson's disease, the anatomical relationship of the two major pallidofugal tracts, namely the ansa lenticularis (AL) and the fasciculus lenticularis (FL) to the Leksell pallidotomy target (LPT) were studied. METHODS: Magnetic resonance (MR) scans of 20 patients with Parkinson's disease were studied. The scans were obtained in the inversion recovery and fast spin echo sequences and viewed in the reverse video mode. RESULTS: The pallidofugal tracts appeared as bands of high intensity on MR scan. FL was wide and extended from the posterior half of the globus pallidus interna (GPi) medially into the internal capsule. AL was narrow, parallel and posterior to the anterior commissure, parallel to and 3 mm above the optic tract, and just beneath the FL. The part of the FL immediately lateral to the internal capsule overlapped the lateral end of the AL. The center of this overlapping area was termed the 'operlapping point' (OP). In all cases, the OP was within the range of LPT. CONCLUSION: It is concluded that the structures in the LPT are FL and AL; and therefore, this procedure could also be known as 'fasciculoansatomy'.

Aged↗
PubMed1995

The golden egg.

Explore the source record for details and available documents.

Humans↗
PubMed1994

Central nervous system aspergillosis. Analysis of 26 patients.

The clinical presentation, risk factors, laboratory data, and neuroimaging and neuropathological findings in 26 patients with autopsy proved central nervous system (CNS) aspergillosis are reviewed. Eleven patients had hematological malignancies (8 underwent bone marrow transplantation), 8 patients underwent liver transplantation, and 3 patients had acquired immunodeficiency syndrome. Four had illnesses resulting in immunosuppression (systemic lupus erythematosus, infected aortic graft, neuroblastoma, and fulminant hepatic failure). The most common presenting clinical symptoms of CNS aspergillosis were fever and a strokelike syndrome. Risk factors for developing CNS aspergillosis included neutropenia, immunosuppressive therapy, low CD4 counts, and retransplantation. Spinal fluid findings were nondiagnostic. Computed tomograms and magnetic resonance scans of the head showed low-density lesions or hemorrhagic infarctions. Most aspergillosis cases occurred in the setting of widely disseminated disease commonly arising from the lung. Pathologically, multiple areas of necrosis throughout the brain were seen. Aspergillus invasion of blood vessel walls was seen microscopically. Amphotericin B with or without flucytosine was not effective treatment.

Adolescent↗
PubMed1994

[Dynamic tibio-fibular fixation with the Rahmanzadeh syndesmosis plate].

In 58 patients of 585 fractures of the ankle we demonstrated the disruption of the tibiofibular syndesmosis. Near to osteosynthetic repair the tibiofibular diastrasis was restored with the syndesmosis-plate by Rhamanzadeh. Postoperative treatment happened plaster-free. Complete weight bearing was achieved pain-dependend after 2 until 4 weeks. This equipment is following from the dynamical fixation of the tibiofibular syndesmosis by preserving the physiological movements between tibia and fibula. Removement of syndesmosis-plate ensued with the remaining osteosynthetical material after one year.

Adult↗
PubMed1994

[Late results of implantation of dual head prostheses in hip para-articular fractures].

In the hospital of Aalen through the years 1985 to 1993 a total of 545 patients have been treated by using a "Duokopf"-prosthesis. The average age was 82.6 years. In a retrospective study the mobility and survival rate after surgery of 109 patients, who had undergone such treatment because of a hip fracture, were found out. The survival rate one year after surgery was within the range of the survival rate of the normal population at that age: The evaluation of the mobility one year after implantation with 57% surviving patients, who are able to walk without aid is a good result. None of the patients showed a protrusio acetabuli. Although the evaluation of the presented results is limited, since, due to the high average age, the mortality rate after surgery was extreme, the Duokopf prosthesis has proved to bring up good long term results.

Aged↗
PubMed1992

Medial canthal tendon reconstruction with nasal periosteum.

Periosteum is a well-known source of tissue used in eyelid and orbital reconstruction. The periosteum medial to the medial canthal tendon, on the lateral wall and bridge of the nose, is an excellent place from which to mobilize this tissue to use as replacement medial canthal tendon. When the medial canthal tendon is lost following cancer extirpation, reconstruction can be accomplished by elevation and rotation of a nasal periosteal flap. Representative cases are presented to demonstrate the technical aspects of the procedure.

Aged↗